How can I help my husband's time management

My husband is a house husband. I work full time and he stays home and takes care of the cooking, cleaning, maintenance, chores, and he goes to school part time. I actually fired him from house husband last month because he wasn't doing anything. He would start and never finish. The house would be half cleaned because he went to do something else instead. He has really bad ADHD, so he finally decided to get on medication and they prescribed him Vyvanse. He's able to focus and get stuff done... The issue is his time management. Stimulants don't help with that. He is more focused now. The issue is he sometimes focuses on the wrong thing. He was supposed to change my cars oil. I had been asking him to for a few days before he started taking his Stimulants and he took he cleaned the entire house top to bottom, bathtub, toilet, guest room and had it smelling like cookies with candles and even decorated for Halloween.... But the oil wasn't changed... Another example, he needed to study for a test and went out and built me an entire entertainment center.... and failed his test the next day. So yeah. We are obviously getting somewhere but I want to help him focus his attention on the right thing.